Re: [PATCH] trace-cmd: fix writing of uncompressed size

Sven Schnelle <svens@xxxxxxxxxxxxx> · Mon, 11 Jul 2022 11:06:35 +0200

Hi,

Tzvetomir Stoyanov <tz.stoyanov@xxxxxxxxx> writes:

> On Mon, Jul 11, 2022 at 10:44 AM Sven Schnelle <svens@xxxxxxxxxxxxx> wrote:
>>
>> Pass &size instead of &handle->pointer. Interestingly this doesn't hurt
>> on x86, but makes trace-cmd fail on s390.
>
> Hi Sven,
> Thanks for testing this code on s390, I've tested it only on x86.
> Please, can you give more information about the trace-cmd failure on
> s390?

I'm running:

# trace-cmd record -p function -F /bin/ls
  plugin 'function'
[ls output follows]
CPU22 data recorded at offset=0x154000
    115345 bytes in size (1269760 uncompressed)
[skipped other CPUs, they didn't record anything]

trace-cmd report doesn't show any trace:

# trace-cmd report
version = 7

trace-cmd dump says:

# trace-cmd dump
 Tracing meta data in file trace.dat:
        [Initial format]
                7       [Version]
                1       [Big endian]
                8       [Bytes in a long]
                4096    [Page size, bytes]
                zstd    [Compression algorithm]
                1.5.2   [Compression version]
        [buffer "", "local" clock, 4096 page size, 1 cpus, 115345 bytes flyrecord data]
        [142 options]
trace-cmd: Unknown error -22
  cannot uncompress section block

Thanks,
Sven